diff --git a/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/XDebugSessionImpl.java b/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/XDebugSessionImpl.java
index 39d1668c8d3e..f28b9b501019 100644
--- a/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/XDebugSessionImpl.java
+++ b/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/XDebugSessionImpl.java
@@ -91,7 +91,7 @@ public class XDebugSessionImpl implements XDebugSession {
   private XDebugProcess myDebugProcess;
   private final Map<XBreakpoint<?>, CustomizedBreakpointPresentation> myRegisteredBreakpoints =
     new THashMap<XBreakpoint<?>, CustomizedBreakpointPresentation>();
-  private final Set<XBreakpoint<?>> myInactiveSlaveBreakpoints = new SmartHashSet<XBreakpoint<?>>();
+  private final Set<XBreakpoint<?>> myInactiveSlaveBreakpoints = Collections.synchronizedSet(new SmartHashSet<XBreakpoint<?>>());
   private boolean myBreakpointsDisabled;
   private final XDebuggerManagerImpl myDebuggerManager;
   private MyBreakpointListener myBreakpointListener;
@@ -420,7 +420,7 @@ public class XDebugSessionImpl implements XDebugSession {
 
   public boolean isBreakpointActive(final XBreakpoint<?> b) {
     ApplicationManager.getApplication().assertReadAccessAllowed();
-    return !areBreakpointsMuted() && b.isEnabled() && !myInactiveSlaveBreakpoints.contains(b);
+    return !areBreakpointsMuted() && b.isEnabled() && !isInactiveSlaveBreakpoint(b);
   }
 
   @Override